The present invention relates to a dispensing device and more particularly to a multi-shot pipetter capable of aspirating a quantity of liquid into a disposable pipette tip, dispensing the liquid in precise dosages, and removing the pipette tip without requiring any direct physical contact with the tip.
There are many laboratory procedures in which it is important to repeatedly pipette a precise dosage of liquid. A common procedure of this type is employed to identify the source of an infection and an antibiotic capable of fighting the infection. To this end, the infectious material is used to inoculate a growth media or culture broth whereafter precise quantities of the inoculum are reacted in accordance with a predetermined schema with various biochemicals, incubated and then examined for classical reactions, as for example, a change or lack of change of color which serves to provide desired information regarding the inoculum.
To employ the above described and similar procedures, it is essential that a precise dosage of inoculum be repeatedly reacted. In addition, it is very often essential that the various instruments that come in contact with the inoculum be maintained sterile and that the technician performing the procedure not come in direct contact with the inoculum.
In view of the above, it is a principal object of the present invention to provide a mechanical device capable of aspirating a supply of liquid into a pipette tip, dispensing predetermined aliquots of the liquid as required and thereafter ejecting the tip without requiring any handling of the tip.